public static ExprNodePropOrStreamSet GetAggregatedProperties(IList<ExprAggregateNode> aggregateNodes)
{
// Get a list of properties being aggregated in the clause.
ExprNodePropOrStreamSet propertiesAggregated = new ExprNodePropOrStreamSet();
ExprNodeIdentifierAndStreamRefVisitor visitor = new ExprNodeIdentifierAndStreamRefVisitor(true);
foreach (ExprNode selectAggExprNode in aggregateNodes) {
visitor.Reset();
selectAggExprNode.Accept(visitor);
IList<ExprNodePropOrStreamDesc> properties = visitor.Refs;
propertiesAggregated.AddAll(properties);
}
return propertiesAggregated;
}
public FilterExprAnalyzerAffector GetFilterExprAnalyzerAffector()
{
var visitor = new ExprNodeIdentifierAndStreamRefVisitor(false);
foreach (ExprNode lhsNode in _lhs)
{
lhsNode.Accept(visitor);
}
var indexedPropertyStreams = new HashSet <int>();
foreach (ExprNodePropOrStreamDesc @ref in visitor.GetRefs())
{
indexedPropertyStreams.Add(@ref.StreamNum);
}
if (indexedPropertyStreams.Count == 0 || indexedPropertyStreams.Count > 1)
{
return
(null); // there are no properties from any streams that could be used for building an index, or the properties come from different disjoint streams
}
var streamNumIndex = indexedPropertyStreams.First();
var keyExpressions = new List <Pair <ExprNode, int[]> >();
var dependencies = new HashSet <int>();
foreach (ExprNode node in _rhs)
{
visitor.Reset();
dependencies.Clear();
node.Accept(visitor);
foreach (ExprNodePropOrStreamDesc @ref in visitor.GetRefs())
{
dependencies.Add(@ref.StreamNum);
}
if (dependencies.Contains(streamNumIndex))
{
return(null);
}
var pair = new Pair <ExprNode, int[]>(node, CollectionUtil.IntArray(dependencies));
keyExpressions.Add(pair);
}
return(new FilterExprAnalyzerAffectorIndexProvision(OperationName, _lhs, keyExpressions, streamNumIndex));
}
public static ExprNodePropOrStreamSet GetNonAggregatedProps(
EventType[] types,
IList<ExprNode> exprNodes,
ContextPropertyRegistry contextPropertyRegistry)
{
// Determine all event properties in the clause
ExprNodePropOrStreamSet nonAggProps = new ExprNodePropOrStreamSet();
ExprNodeIdentifierAndStreamRefVisitor visitor = new ExprNodeIdentifierAndStreamRefVisitor(false);
foreach (ExprNode node in exprNodes) {
visitor.Reset();
node.Accept(visitor);
AddNonAggregatedProps(nonAggProps, visitor.Refs, types, contextPropertyRegistry);
}
return nonAggProps;
}
public static ExprNodePropOrStreamSet GetGroupByPropertiesValidateHasOne(ExprNode[] groupByNodes)
{
// Get the set of properties refered to by all group-by expression nodes.
ExprNodePropOrStreamSet propertiesGroupBy = new ExprNodePropOrStreamSet();
ExprNodeIdentifierAndStreamRefVisitor visitor = new ExprNodeIdentifierAndStreamRefVisitor(true);
foreach (ExprNode groupByNode in groupByNodes) {
visitor.Reset();
groupByNode.Accept(visitor);
IList<ExprNodePropOrStreamDesc> propertiesNode = visitor.Refs;
propertiesGroupBy.AddAll(propertiesNode);
// For each group-by expression node, require at least one property.
if (propertiesNode.IsEmpty()) {
throw new ExprValidationException("Group-by expressions must refer to property names");
}
}
return propertiesGroupBy;
}